The cystic fibrosis transmembrane conductance regulator protein (CFTR) is a cAMP-activated chloride channel which is expressed in epithelial cells in mammalian airways, intestine, pancreas, and testis (Sheppard et al., Physiol. Rev. 79:S23-45 (1999); Gadsby et al., Nature 40:477-83 (2006)). The CFTR chloride channel is known to be associated with a number of diseases and conditions, including cystic fibrosis (CF), polycystic kidney disease and secretory diarrhea.
Diarrheal disease remains an area of high unmet medical need, resulting in approximately 2 million deaths in 2002, of which more than 95% were children under the age of 5 years. Infectious secretory diarrhea, the result of poor sanitation and close living conditions, is responsible for most acute episodes and there is a defined need for an adjunct therapy to be used in combination with existing oral rehydration and antibiotic therapies.
CFTR inhibitors are discussed by Thiagarajah and Verkman in Clinical Pharmacology and Therapeutics (2012): 92, 3, 287-290.